Method of determining a figure of merit of at least one component under test within a signal chain and measurement instrument

Abstract

The present disclosure generally relates to a method of determining a figure of merit of at least one component under test within a signal chain and a measurement instrument. The signal chain has several components and is an internal and/or external signal chain. A measurement signal is captured at a port of the signal chain. An overall figure of merit of the signal chain is determined. The measurement signal is repeatedly captured at the port of the signal chain while altering at least one setting of one of the several components of the signal chain per repetition. The overall figure of merit of the signal chain is determined for each repetition. The at least one setting is altered such that the contribution of the respective component under test to the overall figure of merit of the signal chain is increased with respect to contributions of remaining components of the signal chain.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
         1 . A method of determining a figure of merit of at least one component under test within a signal chain having several components, wherein the signal chain is an internal and/or external signal chain, wherein the method comprises at least the steps of:
 capturing a measurement signal at a port of the signal chain,   determining an overall figure of merit of the signal chain, and   repeatedly capturing the measurement signal at the port of the signal chain while altering at least one setting of one of the several components of the signal chain per repetition, wherein the overall figure of merit of the signal chain is determined for each repetition, and wherein the at least one setting is altered such that the contribution of the respective component under test to the overall figure of merit of the signal chain is increased with respect to contributions of remaining components of the signal chain.   
     
     
         2 . The method of  claim 1 , wherein a respective contribution to the figure of merit is determined for several components under test of the signal chain by repeatedly capturing the measurement signal at the port of the signal chain while altering at least one setting of one of the several components under test of the signal chain per repetition. 
     
     
         3 . The method of  claim 1 , wherein the at least one setting is modified at least such that for several of the components under test of the signal chain at least one component-dependent specific requirement is met at least once. 
     
     
         4 . The method according to  claim 1 , wherein, upon repetitions of capturing the measurement signals, the at least one setting is modified at least such that for several of the components under test of the signal chain an intermodulation product exceeds a component-specific threshold value relative to ground noise at least once. 
     
     
         5 . The method according to  claim 1 , wherein at least one user interface is provided that is connected to a determination circuit. 
     
     
         6 . The method according to  claim 5 , wherein the overall figure of merit of the signal chain and/or a figure of merit of at least one component under test and/or the contribution of individual components to the overall figure of merit is provided via the user interface. 
     
     
         7 . The method according to  claim 5 , wherein at least one external component is added to the signal chain via the user interface and/or the signal chain is defined via the user interface. 
     
     
         8 . The method according to  claim 7 , wherein the at least one setting is altered via the user interface and/or a state of the signal chain is switched during subsequent repetitions via the user interface and/or or a user is prompted via the user interface to change a state of a signal of the at least one external component. 
     
     
         9 . The method according to  claim 1 , wherein the figure of merit is at least one of a noise figure, a third order intercept, a gain, and an attenuation. 
     
     
         10 . The method according to  claim 1 , wherein the figure of merit is measured at an analog-to-digital converter that is part of the signal chain. 
     
     
         11 . The method according to  claim 1 , wherein a sensitivity of the contribution of the respective component under test to at least one of the overall figure of merit, a third order intercept point, a noise figure, and a different figure of merit of the signal chain is determined, wherein the sensitivity gives information about a reliability of identifying the contribution of the respective component under test to the at least one of the overall figure of merit, the third order intercept point, the noise figure, and the different figure of merit when capturing the measurement signal in view of the component's settings. 
     
     
         12 . The method according to  claim 11 , wherein the component's settings are modified upon repetitions of capturing the measurement signal if the sensitivity is below a predetermined threshold value. 
     
     
         13 . The method according to  claim 11 , wherein an output signal is output in case the sensitivity determined is low, wherein the output signal is a notification informing a user about the low sensitivity or a control signal that alters the at least one setting and initializes capturing of an additional measurement signal. 
     
     
         14 . The method according to  claim 11 , wherein the sensitivity determined is output via a user interface. 
     
     
         15 . The method according to  claim 11 , wherein limits for the sensitivity are input via a user interface. 
     
     
         16 . The method according to  claim 1 , wherein a figure of merit of an external component or a contribution of the external component to the overall figure of merit is input via user interface or a database. 
     
     
         17 . A measurement instrument for determining a figure of merit of at least one component under test within a signal chain having several components, wherein the signal chain is an internal and/or external signal chain, wherein the measurement instrument includes circuitry configured to:
 capture a measurement signal at a port of the signal chain,   determine an overall figure of merit of the signal chain, and   repeatedly capturing the measurement signal at the port of the signal chain while altering at least one setting of one of the several components of the signal chain per repetition, wherein the overall figure of merit of the signal chain is determined for each repetition, and wherein the at least one setting is altered such that the contribution of the respective component under test to the overall figure of merit of the signal chain is increased with respect to contributions of remaining components of the signal chain.   
     
     
         18 . The measurement instrument according to  claim 17 , wherein the measurement instrument is coupled to a signal generator capable of generating a measurement signal applied to the signal chain and/or a user interface capable of outputting the contribution of the respective component under test to the overall figure of merit of the signal chain. 
     
     
         19 . The measurement instrument according to  claim 17 , comprising a determination circuit capable of determining the alternation of the at least one setting.